Shortness of Breath / Desaturation 🫁
Clinical guide for shortness of breath, short of breath, and desaturation. Assessment, differential diagnosis, oxygen therapy, and respiratory emergency management for NCHDs.
🧠 Definition
- Shortness of breath or desaturation may reflect underlying respiratory, cardiac, or neurological causes.
- Assess rapidly and escalate early if the patient appears unwell or is deteriorating.
📞 What to Ask / Orders to Make
- Is this new or chronic? Any change from baseline?
- Is the patient alert or confused?
- PMHx: COPD, heart failure, asthma, previous PE/DVT, malignancy.
- Recent infection, aspiration risk, recent surgery, or opioid use?
- Ask nurse to check vitals, administer oxygen, obtain ECG and ABG, prepare for portable CXR.
📋 Common Causes
- Pneumonia (including aspiration)
- Pulmonary embolism (PE)
- Pneumothorax (PTX)
- Acute pulmonary oedema / heart failure
- COPD or asthma exacerbation
- Opiate-induced respiratory depression
- Acute coronary syndrome (ACS)
🧾 History
- Timing and onset (sudden vs gradual), orthopnoea, fever, cough, pleuritic chest pain, leg swelling.
- Risk factors: recent surgery, malignancy, smoking, immobility, known lung or heart disease.
🩺 Examination
- Vital signs: RR, O₂ saturations, heart rate, blood pressure, GCS.
- Look for use of accessory muscles, tracheal deviation, cyanosis.
- Chest exam: auscultate for crackles, wheeze, decreased air entry.
- Check for raised JVP, peripheral oedema, or signs of DVT.
🔍 Investigations
- ABG if altered mental status, hypoxia, or underlying COPD.
- 12-lead ECG to assess for cardiac ischemia, arrhythmias, PE signs (e.g. S1Q3T3).
- Portable CXR to evaluate for consolidation, oedema, pneumothorax.
- CTPA if PE is suspected and renal function allows contrast (consider Wells score first).
- Bloods: FBC, U&E, CRP, troponin, D-dimer, BNP (if heart failure suspected), LFTs.
- Consider COVID swab, sputum and blood cultures if infection suspected.
💊 Initial Management
- Position patient upright. Give oxygen to maintain sats 92–96% (or 88–92% in CO₂ retainers).
- If pulmonary oedema suspected: IV furosemide and escalate early. Nitrates and CPAP are not routine (NICE CG187); senior decision. Nitrates mainly for concomitant ischaemia or severe hypertension; CPAP if severe dyspnoea and acidaemia.
- If PE likely: anticoagulate with LMWH or DOAC if no contraindications.
- If COPD exacerbation: salbutamol + ipratropium nebulisers, corticosteroids, consider NIV if hypercapnic.
- If asthma exacerbation: see Acute Asthma Exacerbation (Adults) — salbutamol (spacer or O₂-driven neb), early steroids, add ipratropium if severe; target SpO₂ 94–98%.
- If pneumonia suspected: start empirical antibiotics, give fluids and oxygen as needed.
- Avoid sedatives and opioids unless for palliative management in respiratory failure.
⚠️ When to Escalate
- Worsening hypoxia or increasing respiratory rate.
- Decline in GCS or new confusion.
- Suspected PE, ACS, or pneumothorax.
- Lack of response to initial treatment or clinical deterioration.
Note Template
Ready-to-use clinical note structure
🕒 16 / 10 / 2026 — 16:16 ATRP re: SOB / ↓ O₂ sats Patient: [age] [sex] Admission Dx: [reason for admission] PMHx: [COPD / asthma / heart failure / cancer / other] 🧾 Hx: • Onset: [sudden / gradual] • Orthopnoea / cough / pain? • Recent infection / aspiration / immobility • Opiates or sedation? 🩺 Exam: • RR: __ SpO₂: __% GCS: __ HR: __ BP: __ Temp: __ • Chest: [AE ↓ / crackles / wheeze] • JVP / oedema / DVT signs 📋 Impression: Likely cause: [pneumonia / PE / fluid overload / COPD / ACS] 📌 Plan: • Sit up, O₂ (target sats 92–95% or 88–92% if CO₂ retainer) • ABG, ECG, CXR, bloods • Treat cause (abx, furosemide, LMWH, nebs) • Escalate if unwell or deteriorating 👤 [Your Name], [Role] IMC: _______
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